(a) Technical Field
The present invention relates to an apparatus for supplying air of a fuel cell vehicle to effectively cool oversupplied air in a fuel cell vehicle.
(b) Background Art
Fuel cell vehicles are equipped with a system that oversupplies air through a compressor when a rapid output is requested. To control the supply of air to the air compressor, an air compression control valve is typically disposed at the rear end of a humidifier in a fuel cell system.
In particular, when the air pressure increases, a partial pressure of the vapor in the air supplied to a stack increases and relative humidity increases as a result. Furthermore, the temperature of the air at the outlet of the compressor is increased by a high compression ratio of the air compressor under a high-output operation condition. Since the high-temperature air decreases the performance of the humidifier, it is necessary to reduce the temperature of the supplied air. To do this, an intercooler is often used for this purpose.
However, the intercooler occupies a large amount of space and a cooling water channel to cool the water is additionally required. Also, the cooling load of a radiator increases because cooling water is generally used. Also, there is a significant load on the water pump, the packaging is difficult to use, and a bypass line required for the system to work is often complicated.
In relation to the above problems, an air supply apparatus for a fuel cell that supplies air to a stack of a fuel cell, and includes: a compressor that generates oversupplied air by compressing external air; a first cooling unit disposed at the downstream side from the compressor, including a vortex tube, and separating the oversupplied air into low-temperature oversupplied air and high-temperature oversupplied air by using energy separation; and a second cooling unit disposed at the downstream from the first cooling unit and cooling the low-temperature oversupplied air supplied from the first cooling unit by using cooling water.
However, in the above solution it is difficult to effectively cool the air. The above system is also more complicated and heavy that is desirable because a separate intercooler is required in order to the system to work properly. Therefore, it was necessary to develop an apparatus for supplying air of a fuel cell vehicle that can effectively cool oversupplied air and supply humidity via a relatively simple system.
The description provided above as a related art of the present invention is just for helping understanding the background of the present invention and should not be construed as being included in the related art known by those skilled in the art.